Ours was modified, we believe very early on by the original owner. The original high/low table top was removed from the adjustable bases, and attached to fixed legs. The port side settee was removed and the table is now there with 2 freestanding chairs. This allows us to move the table around, and even out to the cockpit which is nice. A set of drawers was built against the aft cabin bulkhead on the port side as well, just barely visible in the picture.
On the starboard side, the original L seat was removed, and a bench settee was built that pulls out to a bed. Whoever did the modifications did very nice work, the only way you can tell it didn't originally come like that from the yard are a few bungs in the sole, and the original height adjustable table legs were with the pile of "boat stuff" that came with it and have the hull number written on them from the factory.
I remember seeing the listing photos of your boat and noting the cabinet. I haven't seen another like that, and would think it was maybe also modified in period?